This invention relates to process improvements in melting nitrile polymers and more particularly to the use of additives with the polymer to minimize problems associated with such melting.
In commonly owned, copending application Ser. No. 943,565, filed Sept. 18, 1978, a chemical scavenger in the form of myrcene compound is disclosed to regulate or neutralize the amount of free, acrylonitrile monomer (AN) present during conversion to melt form of a nitrile polymer containing polymerized acrylonitrile monomer preparatory to shaping the melt into a product. Though such compound performs well in regulating AN, it is lubricous by nature and causes feeding problems when a nitrile polymer-myrcene additive blend is charged to a rotary screw-plasticator unit used to carry out such melting. More specifically, the mixture slips on and resists frictional engagement with the surface of the worm screw. The problem is especially aggravated when the polymer particles are in the form of spherical beads having a pronounced tendency to roll on themselves when rubbed together.